Fall is okay keeping in mind that earlier is better. But I'd recommend Spring as it gives the plants way more time to settle in and as a bonus you may actually see blooms the same year. This can be helpful because sometimes you can receive the wrong daylily even from well respected vendors when you order online. If you are very particular about color and height you'd probably want to know sooner rather than later if you got an odd tall purple variety with all the short oranges you ordered.
